The inventive concept relates to semiconductor devices and methods of forming the same.
A field effect transistor (hereinafter, referred to as “a transistor”) is an important constituent element of many semiconductor devices. Generally, the transistor includes a source and a drain that are spaced apart from each other in a semiconductor substrate and a gate covering a channel that extends between the source and the drain. The source and drain may be formed by implanting dopant ions into the semiconductor substrate, and the gate is insulated from the channel by a gate insulating layer that is disposed between the channel portion of the semiconductor substrate and the gate. Transistors are widely used as a switching element and/or a discrete element constituting a logic circuit in semiconductor devices. Recently, operating speeds of the semiconductor devices have been increased, while the sizes of the transistors have been reduced to provide more highly integrated semiconductor devices.